As more and more functions are available in a portable device, the demand for a long use time of the portable device is increasing. Particularly, the battery capacity of the portable device is on the increase in order to lengthen the use time of the portable device. The increase of the battery capacity in turn increases a time to charge a battery. Accordingly, there is a need for a high-efficiency charging technique to reduce a battery charging time.
In general, a charging current supplied to the battery is increased to reduce the charging time of the battery. However, this scheme has limitations in increasing a charging current due to the decrease of a battery lifetime and heat emission. Accordingly, there is a need for a method for effectively reducing the charging time of a battery with high efficiency, other than the method for charging a battery by increasing a charging current.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.